The invention herein relates to deeply embossed sheets and for a method and apparatus for the production thereof. More specifically it relates to such metal sheets suitable for use in reflective thermal insulation devices.
Reflective thermal insulation devices are contructed of metallic enclosing frames containing therein a plurality of spaced-apart reflective metal sheets. A number of such structures are in use in the nuclear power industry, where reflective insulation is widely used for the thermal insulation of the nuclear reactors and associated piping. In one such type of structure, marketed by the Johns-Manville Corporation, the individual reflective metal sheets are separated by protruding standoffs embossed into each sheet, in the manner shown in U.S. Pat. No. 3,190,412. Typical reflective thermal insulation structures for use with piping are shown in U.S. Pat. Nos. 2,841,203 and 3,818,949. Both flat panel and pipe insulations are shown in U.S. Pat. No. 3,028,278. Commercial versions of the structure shown in these patents have been marketed and are in use in various nuclear power plants.
Sequential forming of sheet metal is illustrated in U.S. Pat. Nos. 473,215 and 2,743,518.